Recently I accidentally added a wrong tag to one of my git repositories. So I had to remove a tag from GIT. Here is how I did it:

$> git tag -d release_2.0.0
$> git push origin :refs/tags/release_2.0.0

What these two lines do is:

1. delete tag from local repository
2. pust the update (deletion of tag) to the remote repository

This solution is based on a thread on Stack Overflow (@see the post from Alex Dean).